The patent application DE 30 32 329 A1 describes an air-pressure and flow control valve combination for controlling the stream of compressed air in a pneumatic circuit that includes a pneumatically controlled device. The device has a control and shut-off valve body, which can be moved between open and closed positions. The device also has a flow control valve body, which can be moved into a closed position and into an open position. The device is suitable for industrial compressed air applications in which a reduced pressure on the outflow side is desired. Mentioned as an example is an application in which the valve combination can be connected to both ends of an air cylinder, in order to control the latter either in one direction or in both directions. The air cylinder may be installed in industrial machines of various types. The valve combination is of a very complex construction and its use for pressure vessels for application devices for liquid media is not described.
In the patent application EP 0 039 005 A1, a valve assembly for a pressure cooker is described. This uses a pin protruding from a hood as a pressure indicator. A use for pressure vessels for application devices for liquid media is not described.